The present invention generally relates to a copying apparatus arranged to read out a preliminarily memorized original paper size from a memory and to calculate a converted magnification for effecting a copying operation at the converted magnification and more particularly, to a copying apparatus provided with a paper size memory function having a device for storing an indefinite shape paper size in a memory and a device for reading out the stored indefinite shape paper size, which are provided at an operating section of the copying apparatus.
In a copying apparatus provided with a function for copying an original document onto copy paper sheets of different paper sizes through conversion of magnifications by altering a lens position or paper feeding speed, it is necessary to set the converted magnification for causing the magnification converting copying function to be effected properly.
In the conventional copying apparatus of this kind, as means for setting the converted magnification, there are provided a memory unit storing therein a plurality of definite shape paper sizes and a sensor for detecting the paper size or a key for selecting the paper size, and a device for reading the paper sizes of the original document and copy paper sheet detected by the sensor or selected by the key, out of the memory so as to calculate a ratio therebetween.
However, in the known technique as described above, for subjecting an original document of an indefinite paper size to the converted magnification copying, a long period of time is required for the detection of the paper size by a sensor provided at the lower portion of an original document platform or for inputting lengths of longitudinal and lateral sides of the paper size by the key provided on the operating section. The procedures are extremely troublesome in the method for inputting the paper size by keys. Meanwhile, in the case where indefinite shape original documents of the same size are frequently copied, it is necessary to input the paper size each time, thus requiring complicated operations, with a marked reduction of the working efficiency for the copying apparatus. Moreover, none of the known copying apparatuses are provided with a device for detecting or inputting sizes of indefinite shape copy paper sheets, and as a matter of fact, it has been impossible to effect copying on the indefinite shape copy paper sheets, and therefore, the variable magnification copying function can not be effectively utilized.